The death, which police say they are investigating as either an accident or a crime, comes at a delicate time for the U.S. military in Japan after two U.S. sailors were arrested earlier this month on accusations they raped a local woman.

That case provoked an angry reaction from Japanese officials, and the U.S. military responded by imposing a curfew on its troops in Japan. The curfew restricted military personnel to bases, personal homes or hotels between 11 p.m. and 5 a.m.

The time at which Stiles's body was found suggests he may have been out in breach of this curfew.

He was wearing civilian clothes, not uniform, and didn't have any personal belonging around him, police said. Stiles was stationed at the U.S. base in Sasebo, the city in Nagasaki where Haiki Station is situated.